Known thrust reversers for aircraft jet engine comprise at least one door mounted at the downstream end of the jet generator to pivot about an axis which is transverse and at least substantially diametral to the jet from the jet generator, said door being adapted to pivot between a retracted position in which it forms a part of the nozzle of the engine and an extended position in which it is disposed at least substantially tranversely to said jet.
Three principal types of thrust reversers, in fact, exist:
a first type in which, in retracted position, the doors are disposed around the nozzle without modifying the latter, the extended position, corresponding to the thrust reversal, being obtained by the combinatin of a movement of recoil and a movement of rotation;
a second type in which the doors, in retracted position, form an extension of the nozzle, a simple rotation making it possible to pass into extended position corresponding to thrust reversal; and
a third type described in French Pat. No. 2,348,371, in which the doors themselves form the terminal part of the nozzle without extending the latter, and a simple rotation of the doors about their pivot axis makes it possible, as in the second type, to pass from the folded position of the doors to their extended position, i.e. the position of thrust reversal, or vice versa.
Although operation of the nozzle is, in principle, not modified by a reverser of the first type, the same does not apply to the other systems, and theory and experience show that the obtaining of good performances depends, to different degrees depending on the particular embodiments, on the tightness existing between the nozzle proper and the doors of the reverser.
In a reverser of the third type, the static pressure prevailing in the space defined between the jet generator and the doors is virtually always higher than ambient pressure. It is then necessary to eliminate all the leakages towards the ambient air and to guarantee a tightness which is as perfect as possible between the jet generator and the doors of the reverser. However, in certain configurations, it may be advantageous to allow ambient air to penetrate in said space.
Moreover, in the case of a reverser whose doors form an extension of the nozzle (second type), said static pressure may become lower than ambient pressure, and it may be desirable, in order to obtain the greatest thrust possible, to allow all the ambient air which may be naturally sucked in to enter between the doors and the jet generator.
It is an object of the present invention to satisfy all the requirements set forth hereinabove.